North Korea is providing military goods and training to the African nation of Angola in apparent violation of United Nations sanctions, according to Asian diplomatic sources.

The assistance includes marine engines and replacement parts for North Korean patrol boats sold to the Angolan military within the past six years. Additionally, North Korean military trainers are providing arms and security support to Angolan presidential guards, according to recently obtained information on the transfers.

Similar military support to Uganda and Tanzania was ruled to violate U.N. sanctions by a U.N. panel on North Korea.

According to the sources with access to details of the Angolan military transfers, a North Korean business, Saengpil Associated Co., is in the process of shipping engines and replacement parts for some of the 18 patrol boats that were built for the Angolans since 2011.

Saengpil is part of North Korea’s Green Pine Associated Corp., which has been sanctioned in the past by the United Nations. Both entities are part of the Reconnaissance General Bureau, the North Korean covert action and intelligence organization.

The Saengpil representative behind the military transfers was identified as Kim Hyok-chan, who has been working in Angola since 2008 and has been the lead official in charge of the arms deals between the two countries. Mr. Kim also is a second secretary at the North Korean Embassy in Luanda, the Angolan capital.

North Korean agreements for the patrol boats date to August 2009, when Angolan technicians were trained on repair and maintenance. Construction of the patrol boats, described as PB 100s, began in March 2011. Renewal of the accord for repair and maintenance was concluded in January 2013.

Saengpil is preparing to ship 4.5 tons of patrol boat repair materials via container to Luanda Bay through a North Korean front company in China identified as Beijing New Technology Trading. The goods were described as stainless steel pipes, bolts and nuts that are regarded as dual-use civilian-military items but are to be used for the patrol boats.

Beijing New Technology has been used by the official North Korean firm Changgwang Trading representatives in China as a key vehicle for circumventing U.N. sanctions. Both the U.S. government and the United Nations have sanctioned Changgwang.

Additionally, eight boat engines believed to be destined for the patrol boats are in the process of being sold to the Angolans by Pyongyang. The motors are being disguised in shipping documents as exhaust-gas-related equipment.

The engines are being sent to an Angolan military company known as “MGA/FAA Company Angola.” MGA is the navy company Marinha de Guerra Angola, and FAA is the acronym for the Angolan Armed Forces.

The Obama administration has taken no action in response to reports of North Korean sanctions evasions and violations.

A State Department spokeswoman declined to comment on the illicit military trade between North Korea and Angola. U.N. spokesmen had no immediate comment and referred questions to Spain’s ambassador to the United Nations, Roman Oyarzun, who heads the U.N. sanctions committee on North Korea. Florentino Sotomayor, press counselor at the Spanish U.N. mission, declined to comment.

Hugh Griffiths, head of the U.N. Panel of Experts, also could not be reached for comment.

Support over two decades

Military training by North Korea in Angola includes the dispatch of military instructors who have been providing various support for the past 20 years.

The military advisers normally return to North Korea in December and return to Angola in March. They are housed in a building across the street from the headquarters of the Presidential Guard Unit, known as UGP.

Ten North Korean military trainers are providing martial arts and firearms training to Angolan guards at the Futungo section of Luanda. Another group of 30 North Korean military instructors are engaged in firearms training at a UGP training camp in the Benfica section of Luanda.

The most recent report from the U.N. Panel of Experts on North Korea published in February said similar North Korean police training for Uganda’s security forces violated a 2009 U.N. Security Council resolution. The U.N. sanctions ban “exporting technical training, advice, services, or assistance related to the provision, manufacture, maintenance or use of all arms or materiel.”

The 2009 sanctions were imposed after North Korea conducted an underground nuclear test.

Similarly, an earlier panel report from March 2014 stated that Tanzania’s air force was allowing 18 North Korean military technicians to refurbish Tanzania’s F-7 jet fighters and other military aircraft, also in violation of the 2009 sanctions.

The sources said both Uganda and Tanzania have agreed to halt the military cooperation with the North Koreans, but U.N. officials could not confirm that.

“Based on these cases, North Korea’s support for military training in Angola can be considered illicit activity as well,” said one diplomat.

Bruce E. Bechtol, a former Defense Intelligence Agency official who specialized in North Korean issues, said a large number of countries in Africa continue to use Soviet-era weapons from the 1960s and 1970s, and limited budgets have prevented new arms purchases.

“Thus, North Korea has found a very profitable market for proliferating the vast array of conventional, Soviet-era weapons that it continues to manufacture indigenously,” said Mr. Bechtol, now a professor at Angelo State University. “North Korea is selling everything from tanks to rifles and ammunition, and is also refurbishing many of these older systems for a number nations in Africa.”

Pyongyang also provided military training for several types of units in Africa, and payment is often made in the form of commodities, although cash is also used.

“As in other regions worldwide, North Korea has compiled a sophisticated set of front companies in a network that continues to generate money for the Kim regime,” Mr. Bechtol said. “While arms sales to Iran and Syria have tended to lead the headlines regarding North Korea’s proliferation, their activities in Africa are also very important in bringing in funds and commodities” for North Korea.

The U.N. panel’s report from February said North Korea continues “to defy Security Council resolutions by persisting with its nuclear and ballistic missile programs.” The panel also said it “sees no evidence that the country intends to cease prohibited activities and found widespread evidence of resilience and adaptation in [North Korea‘s] efforts to circumvent the measures imposed by the relevant resolutions.”

North Korean “diplomats, officials, and trade representatives continue to play key roles in facilitating the trade of prohibited items, including arms and related materiel and ballistic missile-related items,” the report said. “In addition to brokering activities, they often serve as shipping companies’ agents or cash carriers.”